Vitamin B5 (Pantothenic Acid)

 Vitamin B₅ (Pantothenic Acid)

(Chick anti dermatitis factor, Filtrate factor)

Introduction

In 1901, a growth factor for yeast, bios was described by Wildiers. In 1933 Williams and his coworkers isolated the crystalline product and called it pantothenic acid because of universal distribution. It was synthesized in 1940 by Stiller and others.

Chemistry

It is peptide-like compound of β-alanine and α-γ-di hydroxy-β, β-dimethyl butyric acid. The physiologically active form of pantothenic acid is coenzyme A (COA).

Properties

The free acid is a

·        viscous, yellow oil

·        soluble in water and ethyl acetate 

·        insoluble in CHCl

·        heat-labile

·        destroyed in acid and alkali

Its calcium compound- calcium pentothenate is a

·        white, crystalline substance

·        highly Soluble in water 

·        insoluble in alcohol

·        quite stable, although autoclaving destroys activity

Distribution

Animal sources

·        Liver

·        kidney

·        egg-yolk

·        yeast

·        milk

Plant sources

·        molasses

·        wheat bran

·        peas

·        sweet potatoes

Functions

(1) Acetyl CoA, also known as active acetate, takes part in the citric acid (TCA) cycle, in combination with choline forms acetylcholine and CHS methyl  also acts as an intermediate in the biosynthesis of cholesterol, fatty acids etc.

(2) Coenzyme A plays an essential part in lipid metabolism. Activation which occurs by formation of a coenzyme A derivative is the first step in fatty acid oxidation.

(3) Pantothenic acid is not present mainly in Co A. A good amount of pantothenic acid is present in the protein-bound form, this protein-bound pantothenic acid is the acyl-carrier proteins (AUP) and required for the biosynthesis of fatty acids

(4) Although this coenzyme is required in the biosynthesis of fatty acids, but coenzyme A is mainly concerned with fatty acid catabolism.

(5) Being a precursor of cholesterol, acyl coenzyme A may produce steroid hormone.

(6) CoA in combination with succinate forms active succinate and helps in the biosynthesis of haemoglobin.

Deficiency signs

·        Dermatitis

·        Fatty liver

·        Degeneration of spinal cord

·        Myelin degeneration of peripheral nerves

·        Gastro intestinal disturbances

·        Alopecia

·        Cornification of the skin

·        Hypo function of adrenal cortex

Daily requirement

Average daily diet contains 10 mg which satisfies this vitamin requirement.